About 6.4 million bitcoin, or 30.2 percent of the supply, has public keys already exposed on the chain. That is the Quantum Alliance’s figure, from a nine-company group that launched on 15 October.
CoinDesk named four members: Hacken, Midnight Foundation, Quantus and Postquant Labs. About 1.1 million of the exposed coins are attributed to Satoshi Nakamoto.
No existing quantum computer can steal any of it. The argument is over when one could. Richard Carback of Postquant Labs calls 2028 a realistic date, while Bryn Bennett of The Vault says nobody knows, only that the risk can be planned for.
The harder split is over what to do with coins whose owners never move them. Changpeng Zhao has suggested freezing Satoshi’s holdings, and the developer Jameson Lopp has proposed restrictions on vulnerable coins. Carback prefers moving them into a trust where verified owners could recover them.
Bennett calls freezing a governance decision for the Bitcoin network, not the industry, and warns it would set a precedent on property rights. Christopher Smith of Quantus says whoever builds the first capable machine will probably take the coins.
There is also no credible price. Bennett says the main expense is coordinating wallets, exchanges, custodians and developers, not the cryptography, and replacement signatures would take more space on the chain, which could push fees up.
The Alliance says it will publish common security tests and migration guidance. For now it has published a number and a disagreement, and Bennett’s own summary was that nobody owns the issue.
